Sources and Types of Radiation
Radiation is constantly around us and has been since the earth was formed. Radiation occurs when energy is emitted by a SOURCE and then travels through a medium, such as air, until it is absorbed by matter. There are two basic types of radiation: # Ionising radiation (e.g. x-rays, alpha, beta, gamma etc.) knocks electrons from atoms producing ions #Non-ionising radiation (e.g. sunlight, microwave ovens, FM and AM radio etc.) usually does not dislodge the electrons and is considered not as hazardous as ionizing radiation Natural background radiation Humans, every day are constantly exposed to small amounts of ionizing radiation from the environment as they carry out their normal daily activities; this is known as natural background radiation. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) identifies four major sources of public exposure to natural radiation: *Cosmic radiation *Terrestrial radiation *inhalation *ingestion Artificial sources of radiation These include: *Medical sources *Industrial sources *Nuclear explosions *Nuclear power EVERYDAY SOURCES 'Wireless Technology' Radio frequency is the energy used in wireless technology. While it can hurt you through heat radio waves are nonionizing radiation. While wireless computer networks don't seem to be a real threat, some scientists say cell phones may increase your risk of cancer. When you use your phone, you're putting the antenna that generates the radio frequency right next to your head; smart phones emit even more radiation no ones knows if this is dangeoruos or not because cell phones have only been in widespread use since the 1990s, not long enough to see long-term effects. 'Tobacco' We all know that tobacco causes cancer. But why? it is from inhaling absorbed by the tabacco plant while in the feild. Even if you are a non-smoker you are still at the risk for second hand smoke that carries the same toxions. Radioactive materials in the atmosphere adhere to sticky tobacco leaves and stay there for the manufacturing process. The use of Apatite--a phosphate fertilizer--increases the radiation absorbed by the tobacco plant. Over the course of decades of inhaling tobacco smoke, the smoker's lungs are damaged, and the smoker -- and folks exposed to the second-hand smoke -- may develop lung cancer 'Smoke Detectors' Smoke detectors make use of the ionising properties of alpha particles. They contain an ionisation chamber that consists of a positive and negative electrode along with a very small amount of an radioisotope Americium-241. 'Security Scans' Two different types of scanners check you and your bags for weapons and other contraband. These machines are X-ray machines. You have to take off your shoes, belt, jacket and place any bags on a conveyor belt so they may be run through a cabinet X-ray machine. Thick walls prevent X-rays from penetrating the surrounding area. The government regulates the amount of radiation the machine can emit and requires alarm systems and locks to prevent mishaps. People pass through an X-ray scanner, called the backscatter system, which uses a low amount of radiation. 'Power Lines' After several decades of research, scientists still don't know a whole lot about the dangers of the electric and magnetic fields produced by high-voltage power lines. The electric charges produce electric fields and the flow of current through the wires produces magnetic fields. In the 1990s, many families and farmers who lived or who had animals near or underneath large power lines came forward to say they believed the electric and magnetic fields had negative effects on their health. The National Institute of Health conducted a study of incidences of childhood leukemia in 1998 and determined that living near power lines was a possible cause, but had no conclusive results While power lines emit their fields in the sky, another danger is lurking underground. Keep reading to find out about radon, a radioactive threat to your health that comes from underneath your home. . 'Radon' Radon is a natural radiation source. Being a noble gas, radon is chemically not very reactive. Radon is the leading source of natural radiation exposure and the second leading cause of lung cancer. It is coloursless, odourless and tasteless. Radon is usually found in low concentrations of rock and soil and it creeps up from cracks and spaces between particles out to the outside air. Medical/Dental Exposure Over the page few decades, doctors have employed an alphabet soup of scans --MRI, CT and PET scans, among others --to detect abnormalities. They use small amounts of radioactive isotopes in nuclear medicine to check for abnormalities in organ systems. All of this is in addition to the old standby, X-rays. While none of these tests have enough radioactivity to pose a threat on their own, many people are worried about the cumulative exposure over a lifetime of medical care. Therapeutic radiation treatments for cancer are different from low-dose diagnostic treatments and may cause permanent harm, but that is minor compared to what will happen if the cancer is not treated. Patients dosed with internal radiotherapy are radioactive for a time and must stay away from other people. Each year, children in the United States undergo approximately 7 million CT scans, and often doctors don't scale down the doses of radiation to account for their smaller sizes. While scientists have not proved that this radiation leads to cancer, some health care professionals say we should be more careful; 'Cosmic Radiation' Cosmic radiation has to do with energy or matter moving through space. There are many forms of radiation that astronomers and physicists know about. Sunlight is a form of electromagnetic radiation produced by the sun, but so is ultraviolet radiation, infrared radiation and gamma radiation. Any heated body produces electromagnetic radiation. They are a form of ELECTROMAGNETIC RADIATION. Like all EM waves, the particles travel at the speed of light. The biggest source of radiation is the sun. Which is a STAR. Solar radiation is radiant energy emitted by the sun, particularly electromagnetic energy. The portion of this ultraviolet radiation that is not absorbed by the atmosphere produces a suntan or a sunburn on people who have been in sunlight for extended periods of time.